Health topics

Sexually transmitted infections


Sexually transmitted infections (STIs) are infections that are spread primarily through person-to-person sexual contact. There are more than 30 different sexually transmissible bacteria, viruses and parasites.

Of the 8 most common STIs, 4 are currently curable: chlamydia, gonorrhoea, syphilis, and trichomoniasis. The other 4 are viral infections and are incurable: hepatitis B, herpes, HIV, and human papillomavirus (HPV). Symptoms or disease due to the incurable viral infections can be reduced or modified through treatment.

Several STIs, in particular HIV and syphilis, can also be transmitted from mother to child during pregnancy and childbirth, and through blood products or tissue transfer.